JPS6310364B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an automatic altitude angle correction device that automatically corrects altitude angle measurement errors that occur when a theodolite is installed obliquely with respect to the horizontal.

Conventionally, this type of device is known from Japanese Patent Application Laid-Open No. 48-77861, in which a prism P placed on the optical path of an altitude angle scale reading microscope L is suspended as shown in the cross-sectional view of Fig. 1. , each other on the altitude scale plate M
The lengths of the two reflecting prisms P ₁ and P ₂ ' are selected so that the optical path length from the 180° opposing scales S and S' to the suspension prism P is equal to the radius R of the altitude scale plate M. . With this configuration, it was possible to eliminate the eccentricity error of the scale plate, and it was also possible to automatically eliminate the altitude angle measurement error caused by the inclination of the theodolite. Prism P ₁ is used for correction adjustment,
It was necessary to replace _P1 ', and there was also the disadvantage that the optical path difference caused by the deviation of the ridge line N of the suspension prism P from the vertical line of the altitude scale plate caused a correction error, making it difficult to obtain sufficiently high accuracy. .

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic altitude angle correction device that solves the above-mentioned drawbacks and is capable of measuring altitude angles with extremely high precision even when installed at an angle with respect to the horizontal axis.

The present invention provides an altitude angle automatic correction device in which luminous fluxes from scales facing each other by 180° on an altitude scale plate are combined by a pendant reflecting member, and images of the two opposing scales are formed on a focus plate. First and second beams are provided between each of the opposing scales and the suspended reflective member for converting the light beam from each of the scales into a parallel light beam.
A collimator lens is arranged, and the first and second collimator lenses are ejected between the suspended reflection member and the focusing plate, and both parallel light beams combined by the suspended reflection member are focused on the focusing plate. An imaging lens for emitting light is provided, and the focal lengths of the first and second collimator lenses are made to match the distance from the center of the scale plate to the scale.

The present invention will be explained below based on examples. Second
The figure is a front view of the altitude angle correction device according to the present invention, FIG. 3 is a plan view thereof, and FIG. 4 is a side view thereof. The light beams from the altitude angle scales S and S' on the altitude scale plate 1 are reflected to the inside of the scale plate by the right-angle reflecting prisms 2 and 2', respectively, and are reflected by the first collimator lens 3,
It becomes a parallel light beam at the second collimator lens 3',
A reflection prism 5 suspended by a suspension member 4a is reached from a predetermined position 4 of the main body (not shown). The suspended reflective prism 5 has reflective surfaces 5a and 5b that are orthogonal to each other, and a ridgeline N as an intersection line of these reflective surfaces is parallel to the scale plate 1 and coincides with the optical axis of the first and second collimator lenses. ing. As a result, the light beams from both scales S and S' are combined in the suspended reflection prism 5, reflected by the reflection prism 6, and condensed by the imaging lens 7. An image of S′ is formed. Here, the right-angle reflecting prisms 2, 2',
Collimator lenses 3, 3', reflection prism 6,
The imaging lens 7 and focusing plate 8 are fixed to the theodolite body (not shown), and the ridge line N of the suspended prism 5 is always located on the vertical line regardless of the inclination of the theodolite body.

In such a configuration, it will be explained using the front view of FIG. 5 that even if the theodolite is installed at an angle, the reading of the altitude angle scale is automatically corrected. Now, the radius of the altitude angle scale plate 1, specifically the radius of the circumference on which the altitude angle scale is engraved, is R, the focal length of the collimator lenses 3 and 3' is f, and the theodolite is aligned with the horizon.
Suppose that it is inclined by an angle θ with respect to HH. At this time, the correct reading point A has moved by =Rθ from the visual axis''. On the other hand, when the light flux reaching the index K provided at the center of the focus plate 8 is traced back, after being reflected by the suspension prism 5, it is always emitted parallel to the horizontal axis due to the original function of the suspension prism, so the actual reading point is B′ is from visual axis′′′′=fθ
move only. However, since f=R, ′′=
Rθ, ′′=, and the actual reading point B′ coincides with the correct reading point A. Therefore, errors caused by the inclination of the theodolite can be automatically and completely eliminated.

Note that since the only operating member is the suspended prism 5, the mechanism can be made small and simple.
Moreover, as mentioned above, since there is a parallel light beam between the collimator lens 3 or 3' and the imaging lens 7,
Errors in focus, magnification, scale reading accuracy, etc. due to deviation of the ridge line N of the suspension prism 5 including the suspension point 4 and during operation from the vertical line of the altitude scale plate do not occur. If the collimator lenses 3 and 3' are each composed of two groups of compound lenses and their focal lengths are made variable, adjustment for correction and the like based on the elastic coefficient of the suspension member becomes very easy.

As described above, the automatic altitude angle correction device of the present invention not only eliminates the eccentricity error of the altitude scale plate, but also makes it possible to read the altitude angle with extremely high accuracy even if the theodolite is installed at an angle. Become.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view of a conventional device, Fig. 2 is a schematic front view of an embodiment according to the present invention, Fig. 3 is a schematic cross-sectional view of the embodiment, and Fig. 4 is a schematic vertical sectional view of the embodiment. , FIG. 5 is a diagram explaining the principle of the embodiment. Explanation of symbols of main parts, S, S'...altitude angle scale,
3... First collimator lens, 3'... Second collimator lens, 4a... Suspended member, 5... Suspended reflective prism, 6... Reflective prism, 7... Imaging lens, 8
...focal plate.

Claims (1)

[Claims] 1. In an automatic altitude angle correction device that combines luminous fluxes from scales facing each other at 180° on an altitude scale plate using a pendant reflecting member, and forms images of both opposing scales on a focus plate, First and second collimator lenses for converting the luminous flux from each scale into a parallel luminous flux are disposed between each scale and the suspended reflective member, and between the suspended reflective member and the focusing plate, an imaging lens for condensing bi-parallel light beams emitted from the first and second collimator lenses and combined by the suspended reflection member onto the focus plate; An altitude angle automatic correction device characterized in that a focal length of the scale is made to match a distance from the center of the scale plate to the scale.